The ratio of BMX bikes in a sporting goods store to mountain bikes is 3 to 2 . The store has 90 BMX bikes . How many mountain bikes does the store have ?
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Answer:

i) [tex]P(X=12)=0.0355[/tex]

ii) [tex]P(X<10)=0.7553[/tex]

iii) [tex]P(X\geq 5)=0.9490[/tex]

Step-by-step explanation:

Let's start by defining the random variable ⇒

[tex]X:[/tex] '' Number of students that will get 7 marks out of 10 in first attempt of a certain Quiz while attempting Quiz on BlackBoard LMS ''

[tex]X[/tex] is a discrete random variable.

The probability of a randomly selected student getting 7 marks out of 10 is 0.4

(This is a data from the question).

Now, if we assume independence between the students while they are doing the Quiz and also we assume that this probability remains constant , we can modelate [tex]X[/tex] as a binomial random variable ⇒

[tex]X[/tex] ~ Bi (n,p)

Where ''n'' and ''p'' are the parameters of the variable.

''n'' is the number of students attempting the Quiz and ''p'' is the probability that a student will get 7 marks out of 10 which is 0.4 ⇒

[tex]X[/tex] ~ Bi (20, 0.4)  in the question.

The probability function for [tex]X[/tex] is

[tex]p_{X}(x)=P(X=x)=\left(\begin{array}{c}n&x\end{array}\right)p^{x}(1-p)^{n-x}[/tex]    (I)

Where [tex]\left(\begin{array}{c}n&x\end{array}\right)[/tex] is the combinatorial number define as

[tex]\left(\begin{array}{c}n&x\end{array}\right)=\frac{n!}{x!(n-x)!}[/tex]

Replacing the parameters in the equation (I) ⇒

[tex]P(X=x)=\left(\begin{array}{c}20&x\end{array}\right)(0.4)^{x}(0.6)^{20-x}[/tex]    (II)

For i) we need to find [tex]P(X=12)[/tex]

Then, we only need to replace by [tex]x=12[/tex] in equation (II) ⇒

[tex]P(X=12)=\left(\begin{array}{c}20&12\end{array}\right)(0.4)^{12}(0.6)^{8}=0.0355[/tex]

For ii) we need to calculate [tex]P(X<10)[/tex]

This probability is equal to ⇒ [tex]P(X<10)=P(X\leq 9)[/tex] and to calculate it we need to sum [tex]P(X=0)+P(X=1)+P(X=2)+P(X=3)+P(X=4)+P(X=5)[/tex]

[tex]+P(X=6)+P(X=7)+P(X=8)+P(X=9)[/tex]

We can do it summing each term or either using any program.

The result is [tex]P(X<10)=P(X\leq 9)=0.7553[/tex]

Finally for iii) we need to find  ⇒ [tex]P(X\geq 5)[/tex]

This probability is equal to ⇒ [tex]P(X\geq 5)=1-P(X\leq 4)[/tex] ⇒

[tex]1-P(X\leq 4)=1-[P(X=0)+P(X=1)+P(X=2)+P(X=3)+P(X=4)][/tex]

Again we can find each term by using the equation (II) or either using a program. The result is [tex]P(X\geq 5)=0.9490[/tex]

Answer:

7

Step-by-step explanation:

65° + 15x + 10 = 180° (co-interior angles are equal)

15x + 75° = 180°

15x = 180° - 75°

15x = 105°

x = 105/15

x = 7

Answer:

its a little blury but i got -3,-9

Answer:

39.5 degrees

Step-by-step explanation:

180-101=79

79/2=39.5

Answer:

-5 is the answer

Step-by-step explanation:

Answer:

No, it doesn't.

Step-by-step explanation:

Whenever there's a "th" at the end of a mathematical word, it means decimal place. A tenth is the first number in a decimal. Ex. (Underlined is the tenth) 1.27. If you round them to the tenth, you would get 20 and 30. Therefore 20 does not round to 30 if rounding to the tenths.

Answer:

It would actually be 20.

Step-by-step explanation:

When rounding to the nearest tenth, you need to pay attention to the  second-to-last digit in the number. If the number is anything from 0 - 4 it rounds down. If the number is anything from 5 - 9, it rounds up.

Feel free to give brainliest.

Have an excellent day!

Answer:

9.28

Step-by-step explanation:

Answer:

33b - 8

Step-by-step explanation:

You solve for the perimeter like you would for any other shape by adding all the sides

The perimeter is side A + side B + side C.

so it's 9b+8 + 12b-8 + 12b-8

Add all the like terms

9b + 12 b + 12b = 33b

8 - 8 - 8= -8

= 33b -8

Answer:

The distributive property states that the product of an expression and a sum is equal to the sum of the products of the expression and each term in the sum.

Answer:

The coordinates of B are: (a, b)=(-2, -6)

Step-by-step explanation:

Let (a, b) be the coordinates of the point 'B'.

As

The midpoint of AB is M(-4, 0)

The coordinates of A are (-6, 6)

The midpoint (x,y) of line joining points (x₁, x₂) and (y₁, y₂)

[tex]x=\frac{x_1+x_2}{2},\:y=\frac{y_1+y_2}{2}[/tex]

-4 = (-6+a)/2  and  0 = (6+b)/2

-8=-6+a          

-8+6=a                  

a=-2

0=(6+b)/2

0=6+b

b=-6

Therefore, the coordinates of B are: (a, b)=(-2, -6)

Answer:

y-5=1/3(x-3)

y=1/3x+4

no standard form

Step-by-step explanation:

Answer:

S = {ABC, ABD, ACD, BCD}

Step-by-step explanation:

We are told that Ariana, Boris, Cecile, and Diego are students in the service club.

Let's denote their names with letters;

Ariana = A

Boris = B

Cecile = C

Diego = D

We are told that Three of the four students will be chosen to attend a conference. This means that the sample space will be a set showing combination of any 3 out of the 4 students.

Thus, sample space is;

S = {ABC, ABD, ACD, BCD}

Answer:

A

Step-by-step explanation:

Answer:

18 months

Step-by-step explanation:

since 1350/75 is 18

Responder:

225 kilometros

Explicación paso a paso:

Dado que :

Velocidad de funcionamiento = 30 km / h

Duración = 45 minutos

Número de días = 10 días

Distancia total recorrida por día:

Duración en horas:

45 minutos / 60 = 0,75 hora (s)

Así, la distancia recorrida por día:

Tiempo de velocidad

30 km / h * 0,75 h = 22,5 km

Por lo tanto, la distancia total recorrida durante 10 días:

Distancia recorrida diariamente * 10

22,5 kilometros * 10 = 225 kilometros

Answer:

a0.50 + b0.30 ≤ $3.00

Step-by-step explanation:

From the question, we have:

Gumballs cost per unit = $0.50

Jawbreakers cost = $0.30

Total budget of Bob = $3.00

Let a represents the number of Gumballs Bob can buy.

Let b represents the number of jawbreakers Bob can buy.

Therefore, inequality that represents the number of gumballs and jawbreakers Bob can buy can be given as follows:

a0.50 + b0.30 ≤ $3.00

The inequality implies that total amount Bob can spend on both gumballs and jawbreakers can be less or equal to $3.00 but cannot be greater than $3.00.

Answer:

Step-by-step explanation:

 c   11). f(x) = - 5x ; f(4) = - 5(4) = - 20

 e   12). f(x) = - x - 3 ; f(8) = - 8 - 3 = - 11

 b   13). f(x) = 8 + 3x - 5 ; f(- 6) = 3(- 6) + 3 = - 15

 a   14). f(x) = [tex]\frac{1}{3}[/tex] x - 4 ; y-intercept is (- 4) and slope of the line is less than 1

 f   15). f(x) = 3 - 3x ; y-intercept is 3 and slope of the line is ( - 3) ⇒ line is going down

129 degrees is the correct answer for the missing angle number 1 :)

Answer:

34

Step-by-step explanation:

8/2 = 4

6 times 5 = 30

30 + 4 = 34

Answer:

Need more information, will get back to you.

Step-by-step explanation:

How many costumes does she want to make?

Answer:

56°

Step-by-step explanation:

The interior angles of a triangle add up to 180.

You would first set up the following problem:

91 + 33 + x = 180

You would now subtract 91 from both sides.

33 + x = 89

You would now subtract 33 from both sides.

x = 56

The value of x is 56 degrees.

Angle of triangle D is 56 degrees.

"A triangle is a simple closed curved made of three segments. A triangle has three sides and three angles, and all three sides and angles are called six elements of the triangle."

We have

Angle sum property of a triangle = [tex]180^{0}[/tex]

<B + <C + <D =  [tex]180^{0}[/tex]

⇒ [tex]91^{0}+33^{0} +x^{0}=180^{0}[/tex]

⇒ [tex]x^{0}=180^{0}-91^{0}-33^{0}[/tex]

⇒ [tex]x^{0}=56^{0}[/tex]

The value of x is 56 degrees.

Hence, angle of triangle D is 56 degrees.

Learn more about triangle here

https://brainly.com/question/8492819

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Answer:

relax jamal dont pull up the 9

Step-by-step explanation:

Answer:

HI FG

Step-by-step explanation:

Answer:

y=-2x+1

Step-by-step explanation:

y-y=m(x-x1)

y-(-3)=-2(x-2)

y+3=-2x+4

-3 -3

y=-2x+1

Answer:

c

Step-by-step explanation:

Answer:

C

Step-by-step explanation:

There is a common ratio r between consecutive terms in the sequence, that is

- 6 ÷ - 3 = - 12 ÷ - 6 = - 24 ÷ - 12 = 2

This indicates the sequence is geometric with n th term

[tex]a_{n}[/tex] = a₁ [tex]r^{n-1}[/tex]

where a₁ is the first term and r the common ratio

Here a₁ = - 3 and r = 2 , thus

a₁₁ = - 3 × [tex]2^{10}[/tex] = - 3 × 1024 = - 3072 → C